Gamma-ray Burst 111022A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:07:23 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     506070,   Seg_Num: 0
GRB_RA:          275.872d {+18h 23m 29s} (J2000),
                 276.051d {+18h 24m 12s} (current),
                 275.109d {+18h 20m 26s} (1950)
GRB_DEC:         -23.668d {-23d 40' 03"} (J2000),
                 -23.661d {-23d 39' 39"} (current),
                 -23.694d {-23d 41' 39"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       6637 [cnts]    Image_Peak=370 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   137     E_range: 15-50 keV
BKG_INTEN:       40685 [cnts]
BKG_TIME:        58008.50 SOD {16:06:48.50} UT
BKG_DUR:         8 [sec]
GRB_DATE:        15856 TJD;   295 DOY;   11/10/22
GRB_TIME:        58024.95 SOD {16:07:04.95} UT
GRB_PHI:         145.91 [deg]
GRB_THETA:        26.76 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     18.62 [sigma]
IMAGE_SIGNIF:    12.41 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +1  +2  +0  +1 -39  +0 
SUN_POSTN:       206.87d {+13h 47m 28s}  -11.08d {-11d 05' 02"}
SUN_DIST:         66.64 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.10d {+10h 04m 24s}   +6.48d {+06d 28' 59"}
MOON_DIST:       124.52 [deg]
MOON_ILLUM:      24 [%]
GAL_COORDS:        8.76, -4.81 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      275.38, -0.34 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 331.31,1.05 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:08:58 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     506070,   Seg_Num: 0
GRB_RA:          275.8642d {+18h 23m 27.40s} (J2000),
                 276.0441d {+18h 24m 10.58s} (current),
                 275.1021d {+18h 20m 24.50s} (1950)
GRB_DEC:         -23.6724d {-23d 40' 20.6"} (J2000),
                 -23.6656d {-23d 39' 56.0"} (current),
                 -23.6990d {-23d 41' 56.4"} (1950)
GRB_ERROR:       6.3 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       5.21e-10 [erg/cm2/sec]
GRB_SIGNIF:      4.79 [sigma]
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58101.09 SOD {16:08:21.09} UT,   76.1 [sec] since BAT Trigger Time
TAM[0-3]:        327.67 237.22 261.49 243.79
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       206.87d {+13h 47m 28s}  -11.08d {-11d 05' 03"}
SUN_DIST:         66.63 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.11d {+10h 04m 27s}   +6.48d {+06d 28' 38"}
MOON_DIST:       124.50 [deg]
MOON_ILLUM:      24 [%]
GAL_COORDS:        8.75, -4.81 [deg] galactic lon,lat of the burst
ECL_COORDS:      275.37, -0.34 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 0.48 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:09:14 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     506070,   Seg_Num: 0
GRB_RA:          275.8642d {+18h 23m 27.4s} (J2000),
                 276.0441d {+18h 24m 10.5s} (current),
                 275.1021d {+18h 20m 24.5s} (1950)
GRB_DEC:         -23.6724d {-23d 40' 20.6"} (J2000),
                 -23.6656d {-23d 39' 56.0"} (current),
                 -23.6990d {-23d 41' 56.4"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       23 [cnts]
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58101.09 SOD {16:08:21.09} UT,   76.1 [sec] since BAT Trigger Time
CENTROID_X:      297.71,  raw= 298  [pixels]
CENTROID_Y:      309.79,  raw= 310  [pixels]
ROLL:            267.79 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   27.80
GRB_POS_XRT_Z:   -14.10
IMAGE_URL:       sw00506070000msxps_rw.img
SUN_POSTN:       206.87d {+13h 47m 28s}  -11.08d {-11d 05' 03"}
SUN_DIST:         66.63 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.12d {+10h 04m 28s}   +6.48d {+06d 28' 35"}
MOON_DIST:       124.49 [deg]
MOON_ILLUM:      24 [%]
GAL_COORDS:        8.75, -4.81 [deg] galactic lon,lat of the burst
ECL_COORDS:      275.37, -0.34 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:09:09 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     506070,   Seg_Num: 0
GRB_RA:          275.8642d {+18h 23m 27.4s} (J2000),
                 276.0441d {+18h 24m 10.5s} (current),
                 275.1021d {+18h 20m 24.5s} (1950)
GRB_DEC:         -23.6724d {-23d 40' 20.6"} (J2000),
                 -23.6656d {-23d 39' 56.0"} (current),
                 -23.6990d {-23d 41' 56.4"} (1950)
GRB_ERROR:       6.1 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       23 [cnts]
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58101.09 SOD {16:08:21.09} UT,   76.1 [sec] since BAT Trigger Time
CENTROID_X:      297.71,  raw= 298  [pixels]
CENTROID_Y:      309.79,  raw= 310  [pixels]
ROLL:            267.79 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   27.80
GRB_POS_XRT_Z:   -14.10
IMAGE_URL:       sw00506070000msxps_rw.img
SUN_POSTN:       206.87d {+13h 47m 28s}  -11.08d {-11d 05' 03"}
SUN_DIST:         66.63 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.12d {+10h 04m 28s}   +6.48d {+06d 28' 36"}
MOON_DIST:       124.49 [deg]
MOON_ILLUM:      24 [%]
GAL_COORDS:        8.75, -4.81 [deg] galactic lon,lat of the burst
ECL_COORDS:      275.37, -0.34 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:11:02 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     506070,   Seg_Num: 0
GRB_RA:          275.872d {+18h 23m 29s} (J2000),
                 276.051d {+18h 24m 12s} (current),
                 275.109d {+18h 20m 26s} (1950)
GRB_DEC:         -23.668d {-23d 40' 03"} (J2000),
                 -23.661d {-23d 39' 39"} (current),
                 -23.694d {-23d 41' 39"} (1950)
GRB_DATE:        15856 TJD;   295 DOY;   11/10/22
GRB_TIME:        58024.95 SOD {16:07:04.95} UT
TRIGGER_INDEX:   137
GRB_PHI:         145.91 [deg]
GRB_THETA:        26.76 [deg]
DELTA_TIME:      -43.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     18.62 [sigma]
IMAGE_SIGNIF:    12.41 [sigma]
LC_URL:          sw00506070000msb.lc
SUN_POSTN:       206.87d {+13h 47m 28s}  -11.08d {-11d 05' 05"}
SUN_DIST:         66.63 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.13d {+10h 04m 32s}   +6.47d {+06d 28' 11"}
MOON_DIST:       124.48 [deg]
MOON_ILLUM:      24 [%]
GAL_COORDS:        8.76, -4.81 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      275.38, -0.34 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 331.31,1.05 [deg].

GCN Circular #12471
S. Immler (CRESST/GSFC/UMD), M. M. Chester (PSU), V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), C. B. Markwardt (NASA/GSFC), K. L. Page (U Leicester), E. Sonbas (GSFC/USRA/Adiyaman Univ.), E. Troja (NASA/GSFC/ORAU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team:
At 16:07:04 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 111022A (trigger=506070). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 275.872, -23.668 which is
```
   RA(J2000) = 18h 23m 29s
   Dec(J2000) = -23d 40' 03"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak structure with a duration of about 15 sec. The peak count rate was ~3000 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 16:08:21.1 UT, 76.1 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 275.8642, -23.6724 which is equivalent to:
```
   RA(J2000)  = 18h 23m 27.40s
   Dec(J2000) = -23d 40' 20.6"
```
with an uncertainty of 6.3 arcseconds (radius, 90% containment). This location is 27 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy.
Swift entered the SAA shortly after detecting this burst, so there are no prompt UVOT data products for this burst at this time.
Burst Advocate for this burst is S. Immler (immler AT milkyway.gsfc.nasa.gov). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:34:42 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     506070,   Seg_Num: 0
POINT_RA:        275.867d {+18h 23m 28s} (J2000)
POINT_DEC:       -23.663d {-23d 39' 46"} (J2000)
POINT_ROLL:      267.794d
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58840.16 SOD {16:20:40.16} UT,   815.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        8.116
N_STARS:         190
X_OFFSET:        433 [pixels]
Y_OFFSET:        538 [pixels]
X_MAX:           1392 [pixels]
Y_MAX:           1497 [pixels]
DET_THRESH:      25
PHOTO_THRESH:    15
SL_URL:          sw00506070000msufc0815.fits
SUN_POSTN:       206.88d {+13h 47m 32s}  -11.09d {-11d 05' 26"}
SUN_DIST:         66.61 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.35d {+10h 05m 24s}   +6.38d {+06d 23' 02"}
MOON_DIST:       124.25 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:        8.76, -4.81 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      275.37, -0.33 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:35:14 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     506070,   Seg_Num: 0
POINT_RA:        275.867d {+18h 23m 28s} (J2000)
POINT_DEC:       -23.663d {-23d 39' 46"} (J2000)
POINT_ROLL:      267.794d
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58840.16 SOD {16:20:40.16} UT,   815.2 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        8.116
N_STARS:         190
X_OFFSET:        433 [pixels]
Y_OFFSET:        538 [pixels]
X_MAX:           1392 [pixels]
Y_MAX:           1497 [pixels]
DET_THRESH:      25
PHOTO_THRESH:    15
SL_URL:          sw00506070000msufc0815.fits
SUN_POSTN:       206.88d {+13h 47m 32s}  -11.09d {-11d 05' 26"}
SUN_DIST:         66.61 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.36d {+10h 05m 26s}   +6.38d {+06d 22' 55"}
MOON_DIST:       124.24 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:        8.76, -4.81 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      275.37, -0.33 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:36:39 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     506070,   Seg_Num: 0
POINT_RA:        275.867d {+18h 23m 28s} (J2000)
POINT_DEC:       -23.663d {-23d 39' 46"} (J2000)
ROLL:            267.794d
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58840.16 SOD {16:20:40.16} UT,   815.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     340993247
X_OFFSET:        752 [pixels]
Y_OFFSET:        857 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       912
Y_GRB_POS:       1017
BINNING_INDEX:   1
IM_URL:          sw00506070000msuni0823.fits
SUN_POSTN:       206.88d {+13h 47m 32s}  -11.09d {-11d 05' 27"}
SUN_DIST:         66.61 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.37d {+10h 05m 29s}   +6.38d {+06d 22' 37"}
MOON_DIST:       124.23 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:        8.76, -4.81 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      275.37, -0.33 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:37:00 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     506070,   Seg_Num: 0
POINT_RA:        275.867d {+18h 23m 28s} (J2000)
POINT_DEC:       -23.663d {-23d 39' 46"} (J2000)
ROLL:            267.794d
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58840.16 SOD {16:20:40.16} UT,   815.2 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     340993247
X_OFFSET:        752 [pixels]
Y_OFFSET:        857 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       912
Y_GRB_POS:       1017
BINNING_INDEX:   1
IM_URL:          sw00506070000msuni0823.fits
SUN_POSTN:       206.89d {+13h 47m 32s}  -11.09d {-11d 05' 28"}
SUN_DIST:         66.61 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.37d {+10h 05m 30s}   +6.38d {+06d 22' 32"}
MOON_DIST:       124.22 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:        8.76, -4.81 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      275.37, -0.33 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 22 Oct 11 16:55:02 UT
NOTICE_TYPE:     Swift-XRT Position UPDATE
TRIGGER_NUM:     506070,   Seg_Num: 0
GRB_RA:          275.8652d {+18h 23m 27.64s} (J2000),
                 276.0451d {+18h 24m 10.83s} (current),
                 275.1031d {+18h 20m 24.74s} (1950)
GRB_DEC:         -23.6733d {-23d 40' 23.8"} (J2000),
                 -23.6665d {-23d 39' 59.3"} (current),
                 -23.6999d {-23d 41' 59.6"} (1950)
GRB_ERROR:       3.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  15856 TJD;   295 DOY;   11/10/22
IMG_START_TIME:  58813.00 SOD {16:20:13.00} UT,   788.1 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       206.90d {+13h 47m 35s}  -11.10d {-11d 05' 44"}
SUN_DIST:         66.60 [deg]   Sun_angle= -4.6 [hr] (East of Sun)
MOON_POSTN:      151.54d {+10h 06m 10s}   +6.31d {+06d 18' 37"}
MOON_DIST:       124.04 [deg]
MOON_ILLUM:      23 [%]
GAL_COORDS:        8.75, -4.81 [deg] galactic lon,lat of the burst
ECL_COORDS:      275.37, -0.34 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
COMMENTS:        TAM values, flux and significance fields are not valid.  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper/docs.php for details.  
COMMENTS:        The probability that this is a serendipitous source in the  
COMMENTS:        SPER window is 1.1% < P(seren) < 2.8%.

GCN Circular #12473
E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich Sternberg Astronomical Institute, Moscow State University
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V. Senik Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk
V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka
K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kislovodsk was pointed to the GRB111022A 29 sec after notice time and 47 sec after GRB time at 2011-10-22 16:07:52 UT. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box. The 5-sigma upper limit has been about 16.6 mag. The object was observed on high (80 deg) zenit distance. The message may be cited.
GCN Circular #12474
S. T. Holland (CRESST/USRA/GSFC), and S. Immler (CRESST/USRA/GSFC) report on behalf of the Swift/UVOT team:
GRB 111022A: Swift/UVOT Non-Detection
UVOT took a finding chart exposure of 150 seconds with the white filter starting 815 seconds after the BAT trigger. This field is very crowded, but no credible afterglow candidate has been found in the initial data products. The 2.7' x 2.7' sub-image covers 100% of the XRT error circle. The estimated 3-sigma upper limit is white > 20.0 mag. No correction has been made for the expected Galactic extinction corresponding to a reddening of E_{B-V} = 0.66 mag. Due to the low Galactic latitude of this burst the extinction is highly uncertain.
GCN Circular #12476
H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), S. Immler (CRESST/GSFC/UMD), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-60 to T+243 sec from recent telemetry downlinks, we report further analysis of BAT GRB 111022A (trigger #506070) (Immler, et al., GCN Circ. 12471). The BAT ground-calculated position is RA, Dec = 275.871, -23.666 deg, which is
```
   RA(J2000)  =  18h 23m 29.1s 
   Dec(J2000) = -23d 39' 58.7" 
```
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 66%.
The mask-weighted light curve shows two peaks: a small peak starting at ~T-18 sec, peaking at ~T-12 sec, merging into the main peak at ~T-8 sec, peaking at ~T-2 sec, and ending at ~T+15 sec. T90 (15-350 keV) is 24.7 +- 3.6 sec (estimated error including systematics).
The time-averaged spectrum from T-17.69 to T+18.57 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.01 +- 0.37, and Epeak of 64.7 +- 13.9 keV (chi squared 63.3 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 2.0 +- 0.1 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T-1.46 sec in the 15-150 keV band is 2.5 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.73 +- 0.08 (chi squared 76.5 for 57 d.o.f.). All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/506070/BA/
GCN Circular #12482
G. Stratta (ASDC), V. D'Elia (ASDC) and S. Immler (CRESST/GSFC/UMD) report on behalf of the Swift-XRT team:
We have analysed 1.1 ks of XRT data for GRB 111022A (Immler et al. GCN Circ. 12471), from 775 s to 1.9 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The refined XRT position is RA, Dec = 275.86481, -23.67325 which is equivalent to:
```
RA (J2000): 18 23 27.55
Dec(J2000): -23 40 23.7
```
with an uncertainty of 3.6 arcsec (radius, 90% confidence). The light curve is consistent with a constant source of mean count rate 1.1e-01 ct/sec. A power-law fit gives an index of 0.2 (+0.6, -0.7).
A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.3 (+0.6, -0.5). The best-fitting absorption column is 6.8 (+4.0, -2.7) x 10^21 cm^-2, in excess of the Galactic value of 2.2 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.4 x 10^-11 (1.0 x 10^-10) erg cm^-2 count^-1.
```
A summary of the PC-mode spectrum is thus:
Total column:	     6.8 (+4.0, -2.7) x 10^21 cm^-2
Galactic foreground: 2.2 x 10^21 cm^-2
Excess significance: 2.8 sigma
Photon index:	     2.3 (+0.6, -0.5)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00506070.
This circular is an official product of the Swift-XRT team.
GCN Circular #12483
Myungshin Im (CEOU/Seoul National Univ), and Yuji Urata (NCU) on behalf of EAFON
We observed GRB 111022A (Holland et al., GCN 12472) in R,I,z, and Y filters with a 1.0-m telescope at Mt. Lemmon, Arizona. The observation started at 10-23-07:52:02 UT, or about 14.5 hrs after the BAT alert, with total integraion of 10 min in each filter. No credible afterglow candidate was found at the enhanced XRT position (Beardmore et al. GCN 12478).
We thank the LOAO operator, J. Youn for his assistance with the observation.
GCN Circular #12487
N. P. M. Kuin (MSSL-UCL) and S. Immler (CRESST/GSFC/UMD) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111022A 815 s after the BAT trigger (Immler et al., GCN Circ. 12471). No optical afterglow consistent with the XRT position (Stratta et al, GCN Circ. 12482) is detected in the initial UVOT exposures.
The field is very crowded and the detection limits may be affected in the white filter by the coincidence loss pattern from a neighboring star.
Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           815          965          147         >21.3
white              815         1287          186         >21.5
v                  972         1859          117         >18.7
b                 1071         1957          117         >19.9
u                 1046         1932          114         >18.9
w1                1021         1908          117         >19.5
m2                 996         1883          117         >21.0
w2                1120         1833           97         >19.0
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.66 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #12490
K. Tokoyoda, Y. Yatsu, Y. Aoki, R. Usui, K. Kawakami, M. Hayashi, S. Song, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed GRB 111022A (S. Immler et al, GCN12471) with the optical three color (g, Rc, and Ic) CCD camera attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan.
The observation started on 2011-10-23 9:16:56 UT (~16.8 h after the burst). We did not find any new point source within the Swift XRT error circle (G. Stratta et al, GCN12482) in three bands.
Photometric results and are listed below. We used GSC2.3 catalog for flux calibration.
```
T0+[day]      MID-UT     T-EXP[sec]      g'             Rc           Ic
---------------------------------------------------------------------------------
 0.71519     9:47:22        3060         >18.4       >16.5       >16.5
---------------------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
```

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Jochen Greiner, last update: 24-Oct-2011 [Disclaimer]